For me, as you pointed out, verify with the prototype what trucks, details are appropriate for your model. If that interests you...
If not, both 70-ton and 100-ton trucks work in the model, look and function well, one requires a little more shimming.
I think we have enough data to safely say the prototype cars are riding with both 70-ton and 100-ton trucks and how that is determined. There obviously is more that can be uncovered, but refer back to the prototype and know that there are/could be exceptions to the rules.
Thanks for prompting the research exercise, was fun learning more about how these numbers play into determining the appropriate wheels for your ride!